Thread-cutting attachment for sewing machines



July 28, 1925. 1,547,567

' A. T. DYE

THREAD CUTTING ATTACHMENT FOR SEWING MACHINES Filed April 22-, 1924 Patented July 28, 1925.

UNITED STATES PATENT OFFICE.-

ALFRED 'I'. DYE, OF ARDMORE, OKLAHOMA.

THREAD-CUTTING ATTACHMENT FOR SEWING MACHINES.

Application filed April 22, 1924. Serial 'No. 708,222.

7 for a shoe or boot sewing machine, andthe primary object of the present invention is v to provide means whereby economy in thread, time, and labor, may be effected in the operation of severing the thread at the end of the stitching operation. Heretofore it has been the custom, at the end of the stitching operation, to withdraw the shoe or boot from the horn of the sewing machine and then cut the thread. In the withdrawal of the shoe,however, a considerable length of thread is unwound from the bobbin and constitutes a waste. Difliculty is then experienced in cutting the surplus length of thread at a point close to the inner surface of the boot or shoe, and frequently surplus lengths of thread are left uncut and cause future'annoyance to the wearer of the boot or shoe. Therefore, the present invention contemplates the provision of an attachment which may be readily mounted upon the horn of a shoe sewing or patch sewing machine and which may be readily manipulated so as to effect a cutting off of the thread close to the inner surface of the boot or shoe being stitched or patched.

In the accompanying drawing:

Figure 1 is a side elevation of the device attached to the horn of a sewing machine which machine is illustrated in a general way and by dot and'dash lines, the view also illustrating a boot upon the horn of the machine in position to be stitched, and

Figure 2 is a detail perspective view of the blade of the attachment.

In the drawings the sewing machine is indicated in general by the numeral 1 and is of the ordinary type, embodying the usual head 2 and horn 3 which horn carries the shuttle (not shown), the needle of the head 2 being indicated by the numeral 4; and being designed, in the ordinary manner, to pierce the boot r shoe arranged upon the horn 3 and carry the thread to the shuttle. By reference to Figure 1 it will be apparent that if it were not for the provision of the attachment embodying the present invention, at the end of the stitching operation, it would be impractical to reach into the boot or shoe and cut the thread with a pair of shears, so that the common practice is to slip the bootor shoeoff from the horn and thensever the thread at the most convenient point in its length. As previously stated, this results in a greater or less length of the thread being unwound from'the bobbin of the shuttle and this constitutes a waste. I

The attachment embodying the invention comprises an attaching member indicated in general by the numeral 5' and formed preferably from a single integral sheet metal blank formed between its ends to provide a sleeve 6, the portions of the blank below the sleeve being united to each other by any suitable securing meansas indicated by the numeral 7 The side portions of the blank below the united portions 7 are formed to embrace the opposite sides and the upper side of the horn 3 so that they form ineffect a split collar 8 which embraces the said horn. The said side portions of the collar are provided at their lower ends with depending ears 9, and a'small 'bolt, 10 is fitted through openings inthese ears and isadapted to be tightened so as to clamp the split collar of the attaching member 5 snugly about the said horn 3. Slidably fitted in the sleeve 6 of the attaching member is a shank 11. The sleeve 6 extends in a direction longitudinally of the upper side of the horn 3, and therefore the stem 11 extends in a like direction above the said horn and in spaced relation to the upper side thereof. Secured in any suitable manner to that end of the stem 11 which is nearer th shuttle carrying or outer end of the horn 3, is the blade of the device which is indicated by the numeral 12, the said blade having a shank portion 13 secured to the said end of the stem and being provided with a transversely extending cutting edge 14 which rests slidably in contact with the upper surface of th horn 3. The blade 12, at the opposite ends of its cutting edge 14, is provided with depending guiding lips 15 which engage against the opposite sides of the horn 3 and which serve to prevent any transverse displacement of the blade 12 with relation to the said horn. As heretofore stated, the stem 11 is spaced above the upper surface of the horn 3 and by referenc to Figure 1 it will be observed that the shank 13 9f the blade is suitably deflected so that the blade will be inclined, in the direction of its cut.- ting edge 14, toward the upper surface of the said horn 8 so as'to have shearing engagement with'the said upper side of the horn. It will also be observed by reference to the said Figure 1 that the cutting edge of the blade 12 is normally positioned a short distance inwardly of the needle opening in the horn 3 and eonsequently in a position where it will not interfere with the ordinary operation of the machine. The blade is normally maintained in this position through the medium of a compression spring 16 which is fitted onto the portion of the stem 11 inwardly of the sleeve 6 and bears at one end against the adjacent end o'f the said sleeve and at its other end against an upwardly bent terminal portion 17 of the said stem, which portion is provided at its upper end with a finger button 18 against which pressure may be exerted, against the tension of the spring 16, so as to longitudinally shift the stem 11 in the direction of the outer end of the horn 3 and thus cause the cutting edge 14 of the blade 12 to coact with the upper side of the horn 3 to shear the thr-ead and cut the same close to the inner side of the boot or shoe. Whenthe finger button 18 is relieved of pressure, the spring 16 will of course return the stem and the blade 12 to normal position as shown in Figure, 1.

While the thread cutting attachment embodyingthej invention, and as illustrated in the drawing, is designed particularly for employment in connection with shoe sewing machines, it will be understood that by modificationavit may be adapted for employment on other types of sewing machines wherever it might be used to'advantage;

Having thus described the invention, what is claimed as new, is:

1. An attachment for the purpose stated comprising an attaching member having a sleeve portion, a stem slidably fitting in the sleeve portion, a spring upon the stem coact? ing with the said member and tending to move the stem in one direction means upon the stem manually engageable to shiftthe stem against the tension ofthe spring, and a blade carried by the saidstem, the said blade having a cutting edge and being provided at its opposite sides and at the ends of its said edge with depending guiding lips.

2. The combination with a sewing ma chine having a work supporting horn and a needle operatively movable with relation to the horn, of a stem slidably mounted upon the horn, means urging the stem in a direction away from the needle, means whereby the stem may be moved toward the needle in opposition to the last mentioned means. and a blade carried by the stem at the end thereof adjacent the needle andhaving a transverse cutting edge in contact with the working 'faceof the horn, the said lade at its pposite sides and at the ends of the cutting edge being provided with depending guiding lips engaging the opposite sides of the said horn. i

In testimony whereof I afi ix my signature. a

ALFRED T. DYE. a s]. 

